In this report we present the experimental study of imaging photoplethysmography in the area of the palm and wrist of fifty-six healthy subjects. We found that the amplitude of the PPG waveform is unevenly distributed...
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In this report we present the experimental study of imaging photoplethysmography in the area of the palm and wrist of fifty-six healthy subjects. We found that the amplitude of the PPG waveform is unevenly distributed over the studied area forming the hot spots with the elevated amplitude. There is clear tendency of the amplitude increasing in the hottest spots with the age of the subject. These observations support the recently proposed model of photoplethysmography in which pulse oscillations of the arterial transmural pressure deform the connective-tissue components of the dermis resulting in periodical changes of both the light scattering and absorption.
This paper presents the possibility of real-time measurement of the diameter of pectin particles during their jellification using an optical correlation method based on the spatial averaging of data.
This paper presents the possibility of real-time measurement of the diameter of pectin particles during their jellification using an optical correlation method based on the spatial averaging of data.
A two-dimensional compound made of one monolayer of Tl and one monolayer of Sn on Si(111) has been found to have a sandwichlike structure in which the Sn layer (having the milk-stool arrangement) resides on the bulkli...
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A two-dimensional compound made of one monolayer of Tl and one monolayer of Sn on Si(111) has been found to have a sandwichlike structure in which the Sn layer (having the milk-stool arrangement) resides on the bulklike terminated Si(111) surface and the Tl layer (having the honeycomb-chained-trimer arrangement) is located above the Sn layer. The electronic band structure of the compound contains two spin-split surface-state bands, of which one is nonmetallic and the other is metallic. Near the Fermi level the metallic band is split with the momentum splitting Δk∥=0.037 Å−1 and energy splitting ΔEF=167 meV. The steep dispersion of the band when crossing the Fermi level corresponds to an electron velocity of ≈8.5×105 m/s, which is comparable to the value reported for graphene. The 2D Fermi contours have almost circular shape with spin texture typical for hexagonal surfaces.
A numerical study is presented of a novel approach to fibre optic SPR-sensor development for biosensing applications. The proposed technique is based on a standard SMF-28 type bent single-mode optical fibre with a thi...
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A numerical study is presented of a novel approach to fibre optic SPR-sensor development for biosensing applications. The proposed technique is based on a standard SMF-28 type bent single-mode optical fibre with a thin metal film applied to its optical cladding. It was shown that by adjusting the curvature radius and the metal film thickness, one can achieve effective coupling between the fundamental mode of the fibre and the surface plasmon mode supported by the metal/surrounding medium interface through the meditation of whispering gallery modes propagating along the bent inner surface of the fibre cladding. This effect is demonstrated to enable refractometric measurements, both in the wavelength and in the intensity-modulated regimes, with a resolution of up to 10-8 RIU. The use of standard noise reduction techniques for intensity-modulated optical signals promises further increase in accuracy.
A combination of scanning tunneling microscopy, angle-resolved photoelectron spectroscopy, ab initio random structure searching, and density functional theory electronic structure calculations was applied to elucidate...
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A combination of scanning tunneling microscopy, angle-resolved photoelectron spectroscopy, ab initio random structure searching, and density functional theory electronic structure calculations was applied to elucidate the atomic arrangement and electron band structure of the (Au,Al)/Si(111)2×2 two-dimensional compound formed upon Al deposition onto the mixed 5×2/3×3 Au/Si(111) surface. It was found that the most stable 2×2-(Au, Al) compound incorporates four Au atoms, three Al atoms, and two Si atoms per 2×2 unit cell. Its atomic arrangement can be visualized as an array of meandering Au atomic chains with two-thirds of the Al atoms incorporated into the chains and one-third of the Al atoms interconnecting the chains. The compound is metallic and its electronic properties can be controlled by appropriate Al dosing since energetic location of the bands varies by ∼0.5eV during increasing of Al contents. The 2×2-(Au, Al) structure appears to be lacking the C3v symmetry typical for the hexagonal lattices. The consequence of the peculiar atomic structure of the two-dimensional alloy is spin splitting of the metallic states, which should lead to anisotropy of the current-induced in-plane spin polarization.
We present a novel optical element: a fibre microaxicon (FMA) for laser radiation focussing into a diffraction-limited spot with a Bessel-like profile as well as for precision laser nanostructuring of metal film surfa...
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We present a novel optical element: a fibre microaxicon (FMA) for laser radiation focussing into a diffraction-limited spot with a Bessel-like profile as well as for precision laser nanostructuring of metal film surfaces. Using the developed FMA for single-pulse irradiation of Au/Pd metal films on a quartz substrate, we demonstrated the formation of submicron hollow microbumps, each with a small spike atop it as well as hollow spherical nanoparticles. The experimental conditions for the controllable and reproducible formation of ordered arrays of such microstructures were defined. The internal structure of the fabricated nanoparticles and nanobumps was experimentally studied using both argon-ion polishing and scanning electron microscopy. These methods revealed a porous inner structure of laser-induced nanoparticles and nanobumps, which presumably indicates that a subsurface boiling of the molten metal film is a key mechanism determining the formation process of such structures.
A simple apertureless dielectric microprobe in the form of a section of the tapered optical fibre was proposed for surface laser nanomodification. This probe enables surface λ /2-localisation of laser beam, as demons...
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A simple apertureless dielectric microprobe in the form of a section of the tapered optical fibre was proposed for surface laser nanomodification. This probe enables surface λ /2-localisation of laser beam, as demonstrated both numerically and experimentally. The controllable formation of single through nanoholes with the minimum size down to 35 nm (∼ λ /15) in the 50-nm Au/Pd film was shown using this probe and a 532-nm pump nanosecond laser. We also report for the first time on the formation of micro- and nanobumps, jet-like microstructures and microholes on optically thick gold films using single nanosecond laser pulses focused through the fibre dielectric apertureless probe. Both the shape and the sizes of the obtained microstructures were demonstrated to be determined by the pulse energy and film thickness.
Triboluminescence properties of chemical compound based on Terbium(Ⅲ)-Tb(АА) Phen- are studied by means of new experimental technique developed in this workIt is found that the synthesized complex manifests 20%...
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Triboluminescence properties of chemical compound based on Terbium(Ⅲ)-Tb(АА) Phen- are studied by means of new experimental technique developed in this workIt is found that the synthesized complex manifests 20% higher integral intensity of triboluminescence in comparison with that for compound based on Europium(Ⅲ) –ТЕА[Eu(DBM)] which is one of best triboluminophores in the visible spectral range.
In this paper, a new approach for synthesis of system of accommodation to faults of navigation sensors of underwater vehicles (UV) is developed and investigated. Proposed system is synthesized by using kinematic model...
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ISBN:
(纸本)9781479960514
In this paper, a new approach for synthesis of system of accommodation to faults of navigation sensors of underwater vehicles (UV) is developed and investigated. Proposed system is synthesized by using kinematic model of UV and data fusion of sensors signals. The advantage of this approach is that it allows detecting and isolating faults in sensors of UV and operatively to compensate their effects at performance of underwater missions in unknown environment with unknown external disturbances, including noised sensor signals.
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